Kaliningrad's fairly strategically useless to them now that every surrounding country's NATO though. The Suwałki Gap between Kaliningrad and Belarus used to be pivotal in potentially re-taking control of Lithuania, Latvia and Estonia. It would have been very difficult for NATO defend them if Russia took the gap. But now those countries are protected by NATO countries all around so Kaliningrad's a lot less useful strategically. Not to mention that there's a strong Kaliningrad independence movement so they're struggling to control it internally as well.

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